4. Calculate the following limits: lim (4 - 3x2) lim x + 20 6 lim a) *-> -2 b) x-+0 2x + 5 x-+3 c - 3 C) - 9 Determine whether f(x) = * + 2x - 8 ; 5 x + 4 is continuous at x = -4. Determine any horizontal asymptotes for f (x) = 2-x + 6. x+2